help-octave
[Top][All Lists]
Advanced

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: zero crossing determination in octave?


From: Carlo de Falco
Subject: Re: zero crossing determination in octave?
Date: Sat, 6 Dec 2008 08:34:06 +0000


On 06/dic/08, at 01:08, Jack Crenshaw wrote:

Um ... I think Patrick was looking for a function that would iterate on the solution. In Matlab, that's fzero. Your function is only a linear approximation, which might be Ok if the data array is dense, but otherwise, NG.

Jack

Jack,
If the "waveform" is given as data samples (x,y) as specified in Patrick's post:

On 05/dic/08, at 20:15, J. Patrick Bedell wrote:
 Just to clarify, I am asking about estimating the zero crossings of
a waveform specified as (x,y) values, not finding the roots of a
polynomial or other function


this is the best you can get.
To use fzero you would need to hava a function to compute y(x) for any given x (and an initial guess). A possible improvement could be to use a smoother interpolant but that only makes sense if you know a-priori that the samples come from a smooth function.
c.


reply via email to

[Prev in Thread] Current Thread [Next in Thread]